Flexible hard surface floor and wall coverings and process therefor



United States Patent O FLEXIBLE HARD SURFACE FLOOR AND WALL COVERINGS AND PROCESS THEREFOR Theodore L. Kuder,'Media, and Richard W. Reaves,

Chester, Pa., assignors to Congoleurn-Nairn Inc.,

Keamy, N. 1., a corporation of New York .No Drawing. Application August 4, 1954 Serial No. 447,898

19 Claims. Cl. 117-76) .Any' raw felt suitable for use in the production of printedfelt base floor coverings can be saturated with any of a number of saturants, including bituminous materials such as asphalt, and synthetic resins such as butadiene-styrene copolymers, chloroprene polymers, and the like. Such saturated felts may be prepared by passing a sheet of raw felt through a tank containing the saturant; or if desired, the saturant may be deposited upon the fibers in a beater in accordance with well-known beatersaturating techniques. The use of beater-saturation is particularly desirable when the saturant is a synthetic resin. After saturation of the felt material, it is simply necessary to permit the saturant to dry prior to conventional use.

In preparing the type of floor and wall covering products with which the present invention is concerned, it has been found necessary to apply one or more coats of a sealing material to the impregnated felt prior to providing a design and wear layer thereon. The seal coat serves a dual purpose of minimizing the tendency of some impregnants to migrate from within and on the felt into the wear layer of the product and to provide a smooth surface on which to deposit the wear layer. Oleoresinous compositions based on drying oils, resins, fillers and/or pigments are most frequently used for this purpose. Elastomeric material. such as styrene-butadiene, acrylonitriIe butadiene, isobutylene-isoprene, polychloroprene and the like have been reported to be suitable for use as impregnated felt seal coats where it is desired to deposit thereon a design and wear layer of thermoplastic vinyl materials such as vinyl chloride. The present invention, however, as aforementioned, is concerned only with the problem of depositing a wear layer and design on impregnated felt with an Oleoresinous and/or alkyd type paint.

Oleoresinous print paints, like Oleoresinous seal coat paints, are comprised of a drying or semi-drying oil base, usually fortified with a resinous material such as rosin, terpene resins, phenol formaldehyde resins, alkyd resins and the like, which function as a binder for pi ments and suitable fillers such as titanium dioxide, calcium carbonate, silicates and the like. Drying agents, accelerators, solvents, and the like are usually employed for their specific functions in accordance with the wellknown practices in the art. Alkyd print paints are similar to Oleoresinous print paints except that an alkydresin is employed in the binder instead of or in conjunction witha drying oil.

Oleoresinous and alkyd paints, hard surface flexible floor and Wall covering felts, felt impregnants, oleoresinous, alkyd and elastomeric seal coats are all well known in the arts, many of them having been in use between fifty and a undred years.

2,856,315 -Patented Oct. 14, 1958 2 In the past, seal coats of the oleoresinous and alkyd type have proved particularly unsatisfactory in regard to decreased distensibility and stiffening during storage with the consequent development of a brittle product. Printed felt base made in the conventional manner exhibits a marked decrease in distensibility in a period as short as one month as compared to its distensibility at the time of production. conditions wherein elevated temperatures on the order of F. are experienced. It is believed that this characteristic of printed felt base produbts which have one or more oleoresinous and/or alkyd seal coats is due to oxidation and/or polymerization of the seal coat compositions which begin at the time of application, continue during storage and are accelerated by elevated temperatures. In connection with narrower widths of printed felt base, decreased distensibility is not a serious prob.

lem as the goods are not ordinarily subjected to severe bending and flexing in use. In connection with the wider products, however, the problem becomes acute resulting in cracking and breaking in the course of unrolling or under other conditions normally experienced in handling and installing the goods.

A standard, test for measuring the distensibility of printed felt base is reported in U. S. Government Specifications for Felt Backed Flooring LLL-F-471 and Federal Specifications LLLL-351a, LLL-L-3S9 and LLL-L-367. The test requires that strips of printed felt base measuring 3 inches by 15 inches be placed over of mandrels of varying diameters. The diameter of the last mandrel upon which the strip is placed immediately priorto cracking on the next succeeding smaller mandrel is reported in inches as the measure of distensibility. Mandrel diameters begin at inch and increase by increments on the order of /2 inch until larger diameters of about 2 inches are reached andthereafter the diameters increase at 1 inch intervals. Prior to the test any material to be tested is conditioned for 24 hours at about 23 C. and 50% R. H. Experience has indicated that a mandrel test reading of 1.5 at the time of manufacture is preferred because of an anticipated reasonable storage period of from 9 to 12 months. During this time the printed felt base products of the prior art ex-- hibit a marked decrease in distensibility. If the initial mandrel test reading is 2 or more, the rate of decrease 7 inches apart and adapted to concurrently move at a slow speed toward a center point. A strip of printed felt base 9 inches long is placed in the gripping means which are thereafter caused to begin movement. The movement automatically stops at a point where the first cracking occurs on the surface of the printed felt base under test. The distance in inches between the gripping means at that time represents the measure of distensibility of the product.

While the industry has experienced only limited difi'iculty in providing acceptable products where at least one dimension of the products was less than about 9 feet, it has not been able to continuously stay within acceptable standards of distensibility for Wider products. For this reason, many attempts have been made to replace the Oleoresinous seal coat with some other material which is capable of functioning as a seal coat, but which provides, in addition, the desired distensibility characteristics at a reasonable cost.

Such attempts have included the use of elastomeric The problem is aggravated under storage assassin base seal coats, which, however, proved unacceptable at the. outset because of the resultant unsatisfactory appearance of the wear layer deposited thereon. It appears that numerous tiny raised points cover the surface of the oleoresinous or alkyd print paint surface after it has been applied toan elastomeric seal coat surface and dried; however, these. apparent raised portions of the paint cannot be felteven with the most sensitive instruments. Some scientists are of the opinion that it is an optical rather than a physical phenomenon. currences of this condition bear a resemblance to the rind or peel of an orange; and, in fact, it is referred to in the industry as orange peel. The reason for the development of orange peel is unknown; however, it is usually associated with a combination of elastomeric and oleoresinous and/or alkyd layers of material, and only infrequently appears inconnection with the usual type of seal coatand print paint.

It is an object of the present invention to provide a printed felt base product having improved distensibility A at the time of production, and one which does not enbrittle beyond thepoint of acceptability in the course of' storage. Another object is to provide such a product which exhibits a minimum amount of orange peel." It isalso an. object to achieve the above results without effecting any product quality deterioration, and in fact, to achieve certain quality'improvemeuts by way of greater distensibility at little or no cost increase. These and other objects will become apparent from the following detailed description of the invention.

It has now been discovered that the above and other objects are achieved by seal coating impregnated felt first" with a synthetic elastomeric material, and thereafter with anoleoresinous and/or alkyd material prior to printing with an oleoresinous and/ or alkyd paint.

All synthetic elastomeric materials are suitable for use inthe present invention. Examples of such materials are: internally or post plasticized copolymers of polyvinyl acetate and acrylic esters, the half butyl esters of maleic anhydride and polyvinyl chloride, copolymers of acrylic acid esters, copolymers of acrylonitrile and butadiene, copolymers of polyvinylidene chloride, the internal or post plasticized homopoly-mer of polystyrene, the tripolymer-of acrylonitrile and butadiene, polyvinyl acetate, and styrene-butadiene. Of these the styrene-butadiene elastomers are preferred because they provide the greatest amount ofdistensibility in the final product at the time ofproduction and a'fter'considerable periods of storage. They makepossible the greatest amount of reduction of, ortheelimination of, the development of orange peel. In addition, they provide a superior bond between the impregnated felt and the first'seal coat, as-well as between the first seal coatandthe second seal coat of oleoresinous and/or alkyd material. It has been found that of the styrene-butadienesthose having a ratio of from about 65% to about 50% polystyrene to from about to about butadiene are preferred in regard to the final productcharacteristic aforementioned. A ratio of about polystyrene to about 40% butadiene is most preferred in that nearly complete elimination of orange peel is-made possible'and a greatly improved distensi bility is effected. A styrene-butadiene elastomer containing' more than polystyrene is less distensible than the preferredproduct while the same elastomer contain ing less than 50% polystyrene results in staining of the printed: final layerby-certain impregnants particularly those of thebituminous type;

The amount of: elastomeric materialtobe used in the firsti coatcomposition: is critical. 7 If it comprises less thanrabout 103% of the total solids of the seal coat, a discontinuousfilmor coating will be obtained. If, on the other-hand, it'exceeds about 25%, the coating will'not function as-a sealer for the bituminous type impregnants and. irradditio'n will increase thecost'of the product so as to render it non-competitive. It is preferred that'the- Exaggerated oc- 4 binder constitute from about 12% to about 15% of the solids in the composition.

The other ingredients of the elastomer base seal coat composition are those normally found in oleoresinous seal coats. Fillers, such as calcium carbonate, silicates, mica, clay, and the like are employed in conjunction with small amounts of additives such as pigments, anticoagulants, dispersing agents, and the like. Since the surface tension of a composition as described abo'veis relatively high and therefore. conducive to the entrapment ofsmall: air bubbles and the subsequent creation of craters and pin holes in. the final. print paint layer, it is preferred that a. surface tension reducing agent be employed. A small amount of a; material such: as a lim'ed rosin-linseed oil varnish, casein, or lecithin has been found to be excellent for this purpose; however,, any drying oil or resin may be used. The surface tension reducing agent generally serves as a binder in addition to the elastomeric material, and therefore, reference herein to the" first coat binder is meant to include both the elastomeric material and any surface tension reducing; agent which also tune-- tions as a binder. Generally, thc'ratio of e'l'a'stomeric ma"- terial resurface tension reducing" material sho'uld be be tween about 18 to 1 and about 3' to 1 depending on the surface tension reducing agent selected. In the case of linseed oil--rosin varnish 9 to 1 is the preferred ratio. Since the above mentioned additives constitute only a minor portion of the-elastomer base first coat composition, allreference' to fillers in the present specification and the claims is meant to include such additives unless otherwise indicated.

In preparing a composition as described above, it is preferred to first prepare an emulsion of the elastomeric material. The manner of accomplishing this is well known andis fully described in U. S. Patent No. 2,498,712 to Ryden and U. S; Patent No. 2,386,764 to Zwicker. Such emulsions usually contain emulsifying agents, i; e., casein, lecithin, and the like, aswell as-from'-about '40% to about 60% water. above may simply be well mixed with the emulsion of elastomeric material while making provision for maintaining a pH in the entire mixture betweenabout- 835" and9 .5. thereby preventing coagulation of theelastomer. The pH adjustment usually'must bedirected upwardly-and there fore a basic material such as ammoniumhydro'xidc may be employed for this purpose.

The following examples are typicalco'tnp'ositions which may-be'employed as the firstseal coat of the'invention.

' The total amount ofwateris govcrned' only'by themea'ns which are selected to apply" the seal' coat tothe irrpregnat'cd' felt base.

EXAMPLE 1- Parts Calcium carbonate 695 Iron oxide (pigment) 5 Tetra sodium pyrophosphate (anticoagulant and dispersing agent) Butadiene-styrene latex (48% solids; 40% butadiene- 60% polystyrene) 180 Rosin-linseed oil varnish 10 Ammonium-hydroxide 2 Water EXAMPLE 2? Mica-clay-calcium carbonate mixture 670:

Polyvinyl acetate (50% solids) s- 240 Casein l0 Ammonium hydroxide 1 Water 110 EXAMPLE 3 Calcium carbonate 640 Copolymer of polyvinylidene chloride (50% solids) 300 All of the ingredients set forth EXAMPLE 4 I V t Parts Calcium carbonate 670 Internally plasticized homopolymer of polystyrene Internally plasticized copolymer of polyvinyl acetate and acrylic ester (50% solids) 240 Rosin-linseed oil varnish Ammonium hydroxide 2 Water 110 EXAMPLE 6 Calcium carbonate 640 Half butyl ester of maleic anhydr'ide and polyvinyl chloride (50% solids) 300 Lecithin 10 Ammonium hydroxide 1 Water 110 EXAMPLE 7 Clay 695 Copolymer of acrylonitrile and butadiene (40% solids) 250 Iron oxide (pigment) 5 Ammonium hydroxide 1 Water 110 EXAMPLE 8 Calcium carbonate 69S Butadiene-styrene latex (50% solids; 50% utadiene- 50% polystyrene) 200 Ammonium hydroxide 1 Tetra sodium pyrophosphate (anticoagulant and dispersing agent) 4 Water 110 Example 1 above incorporates the preferred ingredients of the invention in the preferred manner.

The elastomeric seal coat may be applied to the impregnated felt in any suitable manner. Ordinarily it is most easily applied in the form of the above described water emulsions by doctor coating, roller coating or simply by brushing. It has been found, however, that the elastomeric seal coat must be deposited so as to provide a first coat thickness of at least about 4 mils on standard thickness floor covering felt which measures about 0.054 inch. If less than this is applied, the final product will be subject to staining due to the seeping of certain impregnants particularly of the bituminous type. Further, it has been found that if the elastomeric seal coat is applied in an amount less than 4 mils, a discontinuous or spotted final covering results in the final product. It is difficult, moreover, to provide a product having a uniform appearance in regard to gloss if the elastomer seal coat is less than 4 mils in thickness.

In some cases it may be desired to employ a felt base which is thinner or thicker than the aforementioned standard felt measuring 0.054 inch prior to impregnation. Although a linear relationship does not appear to exist between the thickness of the felt and the amount of first seal coat to be applied, it has been found that about 3 mils first coat thickness is satisfactory on a felt measuring 0.020 inch and about 5 mils is satisfactory on a felt measuring 0.060 inch. Part of the function of the first seal coat is to smooth the felt surface and this is not required to as great an extent on thinner felts as it is on thicker felts. It is for this reason that less seal coat is required on the thinner felt material.

The maximum thickness of elastomeric seal coat which may be applied is also critical. It a thickness of 8 mils is exceeded, the seal coat develops cracks and fissures. The reason for this is unknown; however, it probably is the result of the bulk'of the film at this level. The upper limit remains constant for all thicknesses of felt. The upper limit of first seal coat thickness is of little practical importance because of the cost of material involved.

As aforementioned, it is impossible to' print with oleoresinous or alkyd paint directly on an elastomeric material seal coated, impregnated felt without the occurrence of orange peel, although a considerable amount ofimprovement in distensibility is efiected. In accordance with the present invention, it has been found that a second seal coat of oleoresinous and/or alkyd material greatly minimizes, and in some cases eliminates, the undesirable orange peel appearance in the final product while maintaining the principal portion of the increased distensibility which is apparently due to the elastomeric seal coat. The reason for this is unkonwn since it would be expected that the oleoresinous second coat would result in the same amount of loss of distensibility or embrittling as it did when used in accordance with prior practice.

The second seal coat of oleoresinous material contains the ingredients normally found in oleoresinous seal coats. As aforementioned, they contain drying oils such as linseed oil, tall oil-linseed oil, soy bean oil-china wood oil, fish oil and the like, and resins such as rosin, ester gum, cumar and the like. Alkyd second coats are similar to oleoresinous second coats except that instead of the oleoresinous materials mentioned above, alkyds are employed. These materials are prepared by cooking the alkyds or drying oil and resin mixtures together, diluting them with solvents and emulsifying them so as to obtain a water in oil paint.

The amount of oleoresinous and/or alkyd second coat to be applied depends to some extent on the amount of binder in the composition. It has been found that the binder must comprise at least about 18% of the coating material in order to obtain a film which is not porous, while it may contain up to about 27% binder without developing an undesirable amount of embrittling during storage of the type which the present invention is directed to overcome. In practice, however, no more than about 25% may be used because of economic considerations. Within a range of from about 20% to about 24% binder, orange peel is greatly minimized, and .at the higher levels is substantially completely eliminated, and for these reasons this range is preferred. A composition of the preferred binder content, containing in addition, of course, suitable fillers, may be applied in any manner, such as by doctor coating or by roller coating and the like, and must be applied so as to provide a thickness of about 2 mils. decrease this level of second coat because it also has a smoothing function, the binder content may be increased to the higher permissable levels and thereby permit a slight decrease in the second coat thickness. .In view of equipment limitations and ease of control, it is preferable to employ a level of about 2 mils. There is no reason to exceed this level as no advantages are obtained thereby.

In preparing the product of the present invention, it is simply necessary to coat the impregnated felt with the first seal coat of elastomeric material and allow it to dry. Thereafter the second seal coat of oleoresinous and/or alkyd material is applied and allowed to dry. The wear layer and design may then be printed on the seal coated felt by conventional printing techniques.

To illustrate the improved characteristics of the products of the present invention, the following mandrel test and unsupported bend tests were conducted. In all cases a control was employed comprising asphalt impregnated felt on-which wasv deposited first a 4 mil layer of a composition consisting of 15% linseed oil-rosin varnish,

82% calcium carbonate and 3% of iron oxide, ammonium hydroxide and soap; second, a 2 mil layer of a corn Although it is generally undesirable to i 71" position fcohsisting .-,of 21% -linseed.;oil+rosin;yarnish;and 79%-.calcium carbonate; iand.tl1ird-;,a wear layenlandid sign: of oleoresinous printpaints. Su-chicontrolslindicate an average mandrelv reading of. -1 .42 atth'e. timetheprinte feltbase was.prepared. Themandrel.ttestzvreadingii creased-to. 2.25.;under .raccelerated. storage conditions of: onemonth ratzl Fa At-the end. :of six monthszofi-jactual storageconditions aszexperienced in-rthe normahchannelsr of ccommercaz ;-,the; imandrela test. treading .=:averaged-; 2.0.1; Table-:1 sets forthl. the;icomparative mandrel? testreadingsss for 11116.28 elastomeric sealzcoatrexample's :se.t-.:forth1;pre-? viously;; Tables2 sets :forthitheiiunsupportedtibendztestia readings sfor;=the ;sarne products.:afterminennonths storage 1 at. room itemperaturec The unsupportedrtbend. testnreada ing of :the control.under;thensamenconditions swassA-i... Allafof the samples; which-swere testednwere zcomprised of, an asphalt; impregnatedfelt backing omwhich;:-was' depos:". ited 'aw4 :mihlayer :of relastomeric sseahicoat and :a 2 mil layerrof 21% binde'rcoleoresinous a'secondscoat :on .iWhiCh 7 was. printed .a des1gn ;w1th.:oleores1nous print: zpa1nt-.--

Tabli At Time After 1 Attend Example oi'Promonth at months 0rangeilee1 25 duction 120, Storage-' 0. as l. 1.60 None 1.0 l. 70 1.55 Very Slight. 1.1 1.73 1.157 Do. 1.0 1.80 L60;-l lone. 1.0 l. 75 1. 60 Va y Slight. i. 2 1. 80 l. 65 Slight 1. 0 l. 70 1. 55 None. 1.0 1 1. 70 1.55 Do.

Alfreadings based 'onaverage of 20 samples.

Table.)

After, 9 months. S toragc Example Orange Peel None. Very-Slight NODB. Very Slight. Slight. N one." 7 D0.

A11 readings based on averagebf 20samples.-=

While the invention has been" described with reference to" detailed examples; it is not to-be limited thereby: Various chan'gesin formulation and techniquernay beap-- plied whi'cli are within tlie skill of-" theart. Referenceshould: :be' had to' the =appended=claims for the' limit's of the-scope of-the invention.

What is claimed is :1

1. In a printedffelrbase surface-covering: comprisingan impregnated felt backingyan oleoresinousseal'coat and a,-decorative W621Y' surface, the improvement which comprises-ninterposing between said felt backingand saidoleoresinousseal: coat a uniform layer'cornprising about- 10'percentsto about 25"percent of a rubbery synthetic elastorner and about 75 percent toabout'-90 percent tiller.

2.": In a" printed-"felt base surfacecovering comprising an: impregnated felt backing, an I oleoresinousseal -coat=' andra wear surface comprising a driedbleoresinous print paint, thev improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising about 75 'percentto =about'90" percent filler and about lflpercent toabout 25"per-cent of a butadiene styrene mbbery elastom'er having a ratio of about "l to about 1486 parts of polystyi'eneto 1 part butadiene; v

3. Ina printed'feltb-as'e surface Covering comprising an impregnated felt backing; an oleoresinous seal coat, and.

a wear surface comprising a 'dried' oleoresinous print paint, the improvement which comprises interposing between said felt backing gandisaidioleoresinous seal coat a uniform layer comprising about 75 percent to about percent filler and about 10 percent to about.25perc;e;nt.0f:;- a. butadi'ene-styr enei rubber-y; elastomenhaying .a ratio -10 about 1.5 parts polystyrene to 1 part butadiene'.;-

4. In aprinted felt base surfacecovering comprisinganimpregnated felt backing, an, oleoresinous sealflcoatzx andza wear surface comprisinga dried oleo esinous print;-

paint, the improvementwhich comprises interposing between said felt backing and said oleoresinous seal coat a uniform-layer comprising about '10 'percent 'toabout 25*" percent of a butadie'neestyrene rubberyelastomer having a ratio-of about 1 to about 1.86 parts ofpolystyrene'gto 1 'part butadiene and about 75 percent to about"-90*per-- cent iller, said-uniform layer having-a thicknessordance with the following stable? Minimum. Maximum Flrst' Coat FirstOc-at 5. In a printed felt b-ase-surface'covering comprising an impregnated felt backing, an oleoresinous seal coatcon;

taininggabout 18-percent to-;about;127 Percent b nderm n tj a wear surface comprising a dried oleoresinoustqprint paint, the improvement which comprises :interposing her.

tween said felt backing and said oleoresinous soak coata uniform layer comprising about 10 percent. to abQutrZS' percent of a rubbery synthetic. elastomer selected from the group consisting of plasticized copolymers of polyvinyl acetate-and acrylic esters, half butyl esters of maleic anhydride' and polyvinyl chloride copolymers of "acrylic acid esters, copolymers -of--acrylonitrile and butadiene copolymers of polyvinylidene chloride; plasticized homo-' polymers' of polystyrene; tripolymers-of acrylonitrile and butadiene, polyvinyl acetate, andstyrene-butadiene"and 7 about 75 percent to about 90 percent filler.

6. In. a printed ifelt base surface covering comprising an impregnated felt backing, an oleoresinousseal coat.

containing 20 percent to,24 percentbinder and a wear surface. comprising a dried oleoresinous print paint. the lmprovementwhich comprises interposing-between said felt backing. and saidv oleoresinous; seal coat a uniform layer comprising 12..percent to 15 percent butadiejnestyrene rubbery elastomer-havinga ratio. of about-1 vto.

about.1.86 partspolystyrene to 1 part butadiene and- 85, percent to 88 percent filler."

7. In a printedfeltbasesurface coveringcomprisinganr.

impregnated felt backing, anoleoresinous seal coat;and1c wear surface'comprising a dried oleoresinous print paint,-

the improvement which comprises interposing, between;

said felt backing and said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent.

of a mixture of'rubbery synthetic elastomer and a .compatible surfacetension-reducing agentand about 75 .per-

cent to about 90 percent filler, the ratio of said elastomer.

to said surface tensionreducing agent'being about 3 to l to=about.18 to 1.

8.- In aprinted: felt. base surface covering comprising:-

an impregnated felt backing, an oleoresinous seal" coat. and a wear surface cornprising a. dried oleoresinous'print paint, the improvementv which} comprises-interposing between said'feltbacking and said'oleoresinous. seal coat a uniform layer comprising about :10 percent to about 25 percent of a mixture of rubbery synthetic elastomer and a compatiblesdryingoil varnishand about 75 percent to about90 percent filler; the rationofsaid elastomer to said' dryingoil varnish .Jbei-ngQabout 3 to;1 to-aboutrl8 tol.

9. In a printed felt base surface'covering:comprising.

wear surface comprising a dried oleoresinous print paint, the improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising about percent to about 25 percent of a rubbery synthetic elastomer and about 75 percent to about 90 percent filler.

10. In a seal coated felt for use as a backing for smooth surface coverings comprising impregnated felt and an oleoresinous seal coat, the improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a rubbery synthetic elastomer and about 75 percent to about 90 percent filler.

11. In a seal coated felt for use as a backing for smooth surface coverings comprising impregnated felt and an oleoresinous seal coat, the improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a butadiene-styrene rubbery elastomer having a ratio of about 1 to about 1.86 parts of polystyrene to 1 part butadiene and about 75 percent to about 90 percent filler.

12. In a seal coated felt for use as a backing for smooth surface coverings comprising impregnated felt and an oleoresinous seal coat, the improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a butadiene-styrene rubbery elastomer having a ratio of about 1 to about 1.86 parts of polystyrene to 1 part butadiene and about 75 percent to about 90 percent filler, said uniform layer having a thickness in accordance with the following table:

13. In a seal coated felt for use as a backing for smooth surface coverings comprising impregnated felt and an oleoresinous seal coat containing about 18 percent to about 27 percent binder and about 73 percent to about 82 percent filler, the improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising 12 percent to 15 percent butadiene-styrene rubbery elastomer having a ratio of about 1 to about 1.86 parts polystyrene to 1 part butadiene and 85 percent to 88 percent filler.

14. In a seal coated felt for use as a backing for smooth surface coverings comprising impregnated felt and an oleoresinous seal coat containing about 18 percent to about 27 percent binder and about 73 percent to about 82 percent filler, the improvement which comprises interposing between said felt backing and said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a mixture of rubbery synthetic elastomer and a compatible surface tension reducing agent and about percent to about .90 percent filler, the ratio of said elastomer to said surface tension reducing agent being about 3 to l to about 18 to 1.

15. In a method of producing a printed felt base surface covering comprising an impregnated felt backing, an oleoresinous seal coat and a wear surface, the improvement which comprises depositing on said felt backing prior to the application of said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a rubbery synthetic elastomer and about 75 percent to about percent filler.

16. The method of claim 15 wherein said rubbery synthetic elastomer is a butadiene-styrene rubbery elastomer having a ratio of about 1 to about 1.86 parts polystyrene to about 1 part butadiene.

17. In a method of producing a printed felt base surface covering comprising an impregnated felt backing, an oleoresinous seal coat and a wear surface comprising a dried oleoresinous print paint, the improvement which comprises depositing on said felt backing prior to the application of said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a rubbery synthetic elastomer selected from the group consisting of plasticized copolymers of polyvinyl acetate and acrylic esters, half butyl esters of maleic anhydride and polyvinyl chloride, copolymers of acrylic acid esters, copolymers of acrylonitrile and butadiene, copolymers of polyvinylidene chloride, plasticized homopolymers of polystyrene, tripolymers of acrylonitrile and butadiene, polyvinyl acetate, and styrene-butadiene, and about 75 percent to about 90 percent filler.

18. In a method of producing a printed felt base surface covering which comprises an impregnated felt backing, an oleoresinous seal coat containing about 18 percent to about 27 percent binder and a wear surface comprising a dried oleoresinous print paint, the improvement which comprises depositing on said felt backing prior to the application of said oleoresinous seal coat a uniform layer comprising about 10 percent to about 25 percent of a mixture of rubbery synthetic elastomer and a compatible surface tension reducing agent and about 75 percent to about 90 percent filler, the ratio of said elastomer to said surface tension reducing agent being from about 3 to 1 to about 18 to 1.

19. The method according to claim 18 wherein said surface tension reducing agent is a drying oil varnish.

References Cited in the file of this patent UNITED STATES PATENTS 2,133,886 Beegle et al Oct. 18, 1938 2,624,682 Hazeltine Jan. 6, 1953 2,624,683 Bezman Jan. 6, 1953 2,705,683 Hazeltine et a1 Apr. 5, 1955 2,707,157 Stanton et a1. Apr. 26, 1955 

1. IN A PRINTED FELT BASE SURFACE COVERING COMPRISING AN IMPREGNATED FELT BACKING, AN OLEORESINOUS SEAL COAT AND A DECORATIVE WEAR SURFACE, THE IMPROVEMENT WHICH COMPRISES INTERPOSING BETWEEN SAID FELT BACKING AND SAID OLEORESINOUS SEAL COAT A UNIFORM LAYER COMPRISING ABOUT 10 PERCENT TO ABOUT 25 PERCENT OF A RUBBERY SYNTHETIC ELASTOMER AND ABOUT 75 PERCENT TO ABOUT 90 PERCENT FILLER. 